A Highly Active Catalyst System for Suzuki–Miyaura Coupling of Aryl Chlorides

A series of new Pd­(II) complexes with simple structures were designed and synthesized for Suzuki–Miyaura coupling reactions of aryl chlorides. The new Pd­(II) complexes contain bidentate amine ligands, and their structures were characterized by single-crystal X-ray diffraction. They are highly efficient for Suzuki–Miyaura coupling reactions of aryl chlorides with low catalyst loadings (0.01 mol %) in aqueous media at room temperature. Two possible reaction pathways involving a PdII/0/II and a PdII/IV/II catalytic cycle are proposed, and the mechanism was further investigated using density functional theory (DFT) calculations.